Rotary toothbrush with movable lip guard



Dec. 5, 1950 D. P. GROVER 2,533,107

ROTARY TOOTHBRUSH WITH MOVABLE LIP GUARD Filed Aug. 21, 1946 1N VEN TOR.

Patented Dec. 5, 1950 ROTARY TQDTHBRUSH WITH MOVABLE Lil GUARD Donald B. GrovenChicago, Ill. Application August 21, 1946, Serial No. 691,973

5 Claims.

toothbrushes have been developed heretofore, but

have found very little favor with the public in general. One of the disadvantages of the early type of rotary toothbrush was the absence of any shield partially surrounding the brush element, thus causing some of the toothpaste on the brush to be thrown off and splattered about during the rotation of the brush and permitting the brush to contact the soft inner portions of the mouth causing irritation thereof.

A later development introduced a shield which extended lengthwise of and partially surrounded the rotating brush element to prevent sue-h splattering and mouth irritation. However, actual useage of the type of brush proved unsatisfactory because of the tendency of the lip of the user to be drawn inwardly against the bristles Of the brush and between the bristles and the edge of the shield when the brush was placed against the teeth.

I have been able to overcome the disadvantages of these earlier types of rotary toothbrushes in my present invention, the principal object of which is to provide an electrically driven rotary toothbrush having novel guard means to prevent the lip of the user from being pulled or drawn inwardly against the bristles of the brush element during rotation thereof.

Another object of the invention is to provide a rotary toothbrush having a plurality of spaced guards along the length of the brush element and extending between the bristles thereon whereby the lip of the user is prevented from being pulled or drawn inwardly against the brush during rotation thereof.

A further object is to provide a rotary tooth-- brush having a shield extending lengthwise of and partially surrounding the brush element wherein a plurality of thin guard members extend between the sides of the shield and between the bristles of the brush to prevent the lip of the user from being drawn inwardly between the shield and brush element during rotation thereof.

Still another and more specific object is to providea rotary toothbrush wherein a member in the form of a grille having spaced bars extending between the sides thereof and transversely of the brush element is movably mounted with respect to the brush element, whereby in one position thereof the bars will prevent the lip ofa user from being drawn inwardly against brush, and in another position thereof the brush element is free to be removed for cleaning replacement.

A still further object is to provide a rotary toothbrush having a handle portion and a shaft for drivingthe brush element slidably mounted therein wherein a grille having a lip guard there.- on is movably mounted with respect to the brush element, and wherein locking means are open able upon movement of the grille to one position to lock the shaft against sliding movement and to release the shaft for sliding movement upon moving the grille to another position.

Another object is to provide a modified form of lip guard for a rotary toothbrush wherein a shield or other suitable supporting means extends lengthwise of the brush element and the guard constitutes a plurality of thin bars extending between the sides of the shield and passing below the spindle carrying the bristles of the brush element, whereby the brush element can be easily removed.

Other objects and advantages of the invention will become apparent upon a reading of the following description taken in conjunction with the accompanying drawing in which:

Fig. 1 is a top plan view of the device with a portion thereof broken away and shown in sec tion;

Fig. 2 is a vertical longitudinal section taken substantially along the plane of line 2-2 of Fig. 1;

Fig. 3 is a fragmentary perspective view of one end of the handle portion;

Fig. 4 is a side elevation of the device with a portion thereof in section taken substantially along the plane of line i4 of Fig. 1;

Fig. 5 is a vertical transverse section taken substantially along the plane of line 55 of Fig. 1;

Fig. 6 is a vertical transverse section taken substantially along the plane of line ii@ of I;

Fig. '7 is a vertical transverse section taken substantially along the plane of line ll of Fig. 1;

Fig. 8 is a vertical transverse section taken substantially along the plane of line 88 of F 1,;

Fig. 9 is a perspective view of the device showing the grille in its upper positionwith the brush element removed therefrom; and

Fig; 10 is a fragmentary perspective view of one end of the device showing a modified form of lip guard.

Briefly described, the invention herein consists primarily in the provision of guard means against which the lip of the user of the rotary toothbrush will ordinarily bear during the use thereof to guide or direct the lip to the outer side of the shield and thus prevent the lip from being drawn inwardly between the brush element and the shield. When the rotary brush is in use and placed against the teeth, the brush element is usually designed to rotate in a manner to brush the teeth away from the gums, which is considered by dentists as the proper way to brush teeth. In actual practice where no lip guards are present it has been found that brushes of this character disclosed in the prior art have a tendency to pull the lip inwardly against the bristles of the brush, and if a shield is present the tendency is to pull the lip between the brush and the edge of the shield. Serious injury to the lip may not necessarily result, but such an experience is decidedly unsatisfactory and unpleasant, discourages further use of the device by causing rawness and bleeding of the lip and has been considered the principal reason for the lack of commercial success of earlier rotary toothbrushes. It will be obvious that numerous specific forms of guard means may be designed to accomplish the main purpose of this invention and several 1 of these forms have been disclosed herein.

Referring now more particularly to the drawings, the main body or handle portion i may assume any desired shaped and size, but preferably it should be of a size convenient to be held in the hand and should be formed of a plastic or other similar non-conducting material. Broadly speaking, the handle portion may embody its own electric motor, or it may be driven from an external source. The present form of the invention as disclosed herein contemplates the use of a rotatable shaft within the handle which may be easily connected to a flexible shaft for pur poses of driving the brush. In the specific form shown, the handle portion l is provided with a longitudinal openin 2 adapted to receive a rotatable shaft 3. One end of the opening is provided with a bearing 4 and the opposite end has a similar bearing 5 to thereby rotatably support the shaft 3 at each end thereof. The rear or outer end of the shaft 3 may be provided with a transverse rib 6 adapted to be received in a suitable opening or socket in a flexible shaft (not shown) for purposes of driving the brush. The rear of the handle may also be provided with radially extending ribs 1 to securely hold the end of the flexible shaft in place,

The rear end of the opening 2 is enlarged slightly as indicated by the numeral 8, and the shaft 3 is provided with an annular groove 9 adapted to receive a retaining ring it. This ring is received partially in the groove 9 and partially in the enlarged portion 8 of the opening 2 whereby a longitudinal sliding movement of the shaft 3 may take place when it is not connected for use in order that the brush element may be removed therefrom, as will be presently observed.

A shield or other suitable supporting means H is provided at the forward end of the handle and may be integral therewith or otherwise suitably secured thereto. The shield H extends longitudinally of the brush element and partially surrounds it as shown. The forward end of the shield H has an upwardly extending end l2 havconstitutes what may be termed a grille, generally indicated by the numeral l8, which has alternate bars l9 and spaces 29 along the length thereof. The bars l9 extend transversely of the grille frame and are preferably arched so as to pass over the top of the spindle M. The spaces 20 permit the bristles l5 of the brush element to extend upwardly therethrough and perform the cleaning function when the grille is in its lower position as shown in Figs. 1, 2 and 4. The grille may be movably mounted in any suitable manher so that it can be removed from the brush element in order to permit the brush element itself to be taken out or its supporting means. In the particular form of the invention shown herein, the grille is pivotally mounted by means of the pivot pins 2! at its rear end to the sides of the handle portion I, so that it may be elevated to the dotted line position shown in Fig. 4 and the full line position shown in Fig. 9.

The bars IQ, extending across the sides of the grille, will clearly act as lip guards so that when the toothbrush is in use and the brush element is rotating, the lip of a user will be prevented !from being drawn inwardly between the edge of the shield l l and the brush element itself which, .as has already been pointed out above, is highly undesirable.

Another feature of this form of the invention involves the use of a locking means to lock the slidable shaft 3 in its forward position when the grille or lip guard is lowered to thereby retain the brush element in place. The specific form of this locking means which I have de- Vised includes a pin 22 which extends inwardly from the upper edge of each of the pivot pins 2|. These pins or projections 22 extend inwardly between the sides of an annular groove 23 adja cent the forward end of the shaft 3. The rear edge of this annular groove is tapered as at 24. In the operation of this locking means it will be evident that when the grille is in its lower position as shown in Figs. 1, 2 and 4, the projections 22 will be in the position shown in Fig. l, where the shaft 3 is in its full forward position. When the grille is elevated, it will rotate the pivot pin 2| which will carry the projections 22 rearwardly, thus allowing the shaft 3 to move rearwardly until the forward shoulder or side of the annular groove 23 comes against the projections 22. This will permit a sufficient rearward movement of the shaft 3 to disengage its forward end from the transverse section 16 on the spindle l4 and thus permit removal of the brush element. When the brush element is reinserted, the grille may be lowered and will automatically move the shaft 3 forwardly and lock it in this position during use of the device.

It should be noted here that it is immaterial as far as the invention is concerned how the grille is actually made or formed. That is to say, it may be a solid piece of material, such as plastic, after which the slots 20 may be cut therein leaving the bars l9. On the other hand, the framework of the grille may be first formed and bars l9 secured thereto to form the spaces 20.

of the invention may also be termed a grille which may be composed of the lower supporting member and the spaced bars 26. The member 25 may be in the form of a shield and the bars 25 secured thereto, or the entire grille may be formed of a single piece of material and have grooves cut transversely therein to provide the bars 26.

It will be noted that in both forms of the in vention the bars l9 and the bars 26 both extend upwardly adjacent the brush element at each side of the shield so as to prevent the lip of the user from being drawn inwardly between the edge of the shield and the brush element during rotation thereof.

From the foregoing description it will be evident that I have provided a novel improvement in the art of rotary toothbrushes wherein suitable guard means are provided to prevent the lip of the user from being drawn inwardly against the brush or between the shield and the brush element when such a shield is used. It will be clear that if it is desired to omit the shield, then other means of securing the guard members in place may be used. It will also be clear that changes may be made in the form, construction and arrangement of parts from any of those disclosed herein without in any way departing from the spirit of the invention or sacrificing any of the attendant advantages thereof, provided, how ever, that such changes or modifications fall within the scope of the claims appended hereto.

Having thus described my invention what I claim as new and desire to secure by Letters Patent of the United States is:

1. A rotary toothbrush of the class described, comprising a handle portion, a brush element rotatably mounted at one end of said handle portion, and a grille pivotally mounted on said handle portion and extending longitudinally of said brush element having transverse bars and slots therein, the bristles of said brush extending through said slots and said bars adapted to pre vent the lip of a user from being drawn inwardly against said brush element during rotation thereof.

2. A rotary toothbrush of the class described, comprising a handle portion, a brush element rotatably mounted at one end of said handle portion, a shield extending longitudinally of and partially surrounding said brush element, and a grille having transverse slots and bars therein pivotally mounted on said handle portion and adapted to rest on said shield when in normal closed position, the bristles of said brush extending through said slots and said bars adapted to prevent the lip of a user from being drawn inwardly between the shield and the brush element during rotation thereof.

3. A rotary toothbrush of the class described, comprising a handle portion, a brush element Cir rotatably mounted at one end of said handle portion, a shield member extending longitudinally of and partially surrounding said brush element, and a grille member having transverse slots and bars therein also extending longitudinally of said brush element opposite said shield member, means for mounting one of said members for movement away from said brush element to per unit removal of said brush elemenhthe bristles of said brush extending through the slots in said grille member, and said bars adapted to prevent the lip of a user from being drawn inwardly between the shield member and the brush element during rotation thereof.

4. A rotary toothbrush of the class described, comprising a handle portion, a rotatable shaft extending lengthwise of said handle portion and mounted for longitudinal sliding movement therein, a brush element having a spindle adapted to be removably moun ed at one end of said shaft and rotatable therewith, a shield partially surrounding said brush element, lip guard means movably mounted at one end of said handle portion, and locking means operable upon movement of said lip guard to lock said shaft against sliding movement in one position thereof and to release said shaft for sliding movement to permit said brush element to be removed therefrom.

5. A rotary toothbrush of the class described, comprising a handle portion, a rotatable shaft extending lengthwise of said handle portion and mounted for longitudinal sliding movement therein, a brush element having a spindle adapted to be removably mounted at one end of said shaft and rotatable therewith, a shield partially surrounding said brush element, lip guard means I pivotally mounted at one end of said handle portion and movable to a lower position adjacent said brush element when in use and to an upper position away from said brush element, and locking means operable upon movement of said lip guard to lower position to lock said shaft against sliding movement, and to release said shaft for sliding movement when in upper position to permit said brush element to be removed therefrom.

DONALD P. GROVER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

